Yeap! tell your employees that time has come where you need someone in charge, dependable responsible and be able to handle the crew, ask'em if one of them would be interested in the position or if you should look somewhere else. Most of the times when somebody is really ambitiuos they'll come forward and say, I can do it, make sure all of your workers know that the person thst is going to be in charge will be telling everybody what to do, and tell your foreman that he'll be the one responsible for anything good or bad.

I usually tell all my workers that my foreman can fire them if he thinks they not performing the way they're suposse to, and I tell my foreman that if somebody is not working then tell me about it I'd talk to and if happens again they're history.